Colonic Bleeding Due to Histoplasma and Mycobacterium Coinfection in Renal Transplant Patient

Introduction: Histoplasmosis is a rare infectious condition caused by the fungus Histoplasma capsulatum that can be presented from asymptomatic to severe forms. Tuberculosis, still an endemic infection in some developing countries, can also have variable clinical presentations. Both diseases involve the lungs mostly, but in immunocompromised patients, especially those with advanced HIV infection and transplant patients, disseminated forms are more frequently found. Gastrointestinal involvement is unusual, and digestive bleeding is an even rarer complication. Case presentation: We report the case of a 39-year-old female who was diagnosed with a Mycobacterium tuberculosis and Histoplasma capsulatum coinfection occurring 11 years after a living-donor-related renal transplant. The patient presented a severe gastrointestinal bleeding caused by an ulcer in the ascending colon. She improved after a combined treatment with tuberculostatic and fungicidal drugs. Conclusions: Simultaneous gastrointestinal involvement by histoplasmosis and tuberculosis, presenting as severe digestive bleeding, with minimal respiratory symptoms associated, make this an extremely rare case and a diagnostic challenge. Therefore, it is important to keep a high clinical suspicion of opportunistic infection, especially in immunocompromised patient who presents with LGB.